Tunnel deformation monitoring and analysis method based on grid projection point cloud processing technology

Abstract

Provided in the invention is a tunnel deformation monitoring and analysis method based on a grid projection point cloud processing technology. For a tunnel surface point cloud model obtained by a three-dimensional laser scanner, a tunnel design surface model is constructed and unit grid processing is carried out; projection of unit grids on a tunnel surface point cloud model is carried out; fitting of point clouds in a projection range is carried out to form a plane quadrangle; a distance between the center of the plane quadrangle and the projection center at the central axis of the tunnel iscalculated; differences of deformation directions of point clouds of corresponding projection areas of the unit grids are determined; and deformation monitoring data screening is carried out and colorprocessing is carried out on the tunnel design surface model based on the deformation amounts of the corresponding positions of the unit grids, thereby realizing overall analysis and visual processing of the tunnel deformation monitoring. According to the invention, the tunnel surface point cloud model obtained by the three-dimensional laser scanner is processed by using the grid projection pointcloud processing technology, so that tunnel surface point cloud deformation caused by influences of tunnel surface peeling, block falling or attachments can be identified and the monitoring and analysis errors can be avoided. On the basis of the unit meshing and deformation amount visual processing of the tunnel design surface model, the overall analysis of the deformation of the tunnel structureis realized conveniently and thus the visual effect is enhanced.

Description

Technical field: [0001] The invention belongs to the technical field of tunnel deformation monitoring, and in particular relates to a tunnel deformation monitoring and analysis method based on grid projection point cloud processing technology. Background technique: [0002] At present, the traditional method of tunnel deformation monitoring is mainly to embed several deformation monitoring points in the tunnel arch and on both sides of the tunnel every other mileage, and use the total station or level to measure the elevation change of the arch monitoring points as the settlement of the tunnel arch. A total station or an extensometer is used to measure the change in the distance between two deformation monitoring points as the amount of tunnel convergence deformation in the direction connecting the two measuring points. [0003] The 3D laser scanner can automatically and quickly acquire high-density point cloud data on the surface of the target object, and the measurement ac...

AI Technical Summary

Problems solved by technology

[0007] 1. The number of deformation monitoring points in the traditional method is small, and it is impossible to analyze the overall deformation of the tunnel. The monitoring of tunnel convergence deformation reflects the shrinkage or expansion deformation of the tunnel through the distance change between two monitoring points, and cannot accurately reflect the tunnel's direction towards the center of the section. The amount of change in the radial direction and the poor operating environment in the tunnel lead to large measurement errors and low operating efficiency. The information feedback forms are mainly digital tables and graphs, and the visualization effect is poor;

[0008] 2. The tunnel deformation monitoring method based on 3D laser scanning technology can solve the deficiencies of the above-mentioned traditional methods, but the point cloud data difference will also be caused when the tunnel surface has peeling, falling blocks or attachments, which is not the deformation of the tunnel structure If it is not eliminated, the monitoring result obtained is not the real deformation of the tunnel structure;

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